Blind stitch sewing machine



y 1932- c. w MUELLER 1,860,901

BLIND STITCH SEWING MACHINE Filed Sept. 14, 1929 5 Sheets-Sheet l Gttomeg y 31, 2; c. w. MUELLER BLIND STITCH SEWING MACHINE 5 Sheets-Shet 2 Filed Sept. 14. 1929 May 31, 1932. c. w. MUELLER,

BLIND STITCH SEWING MACHINE 3. Sheets-Sheet 3 Filed Sept. 14, 1929 W 2 m% 74.1. k w \\k wlliuv/l km N N U x u SW. m @w w u n I M. W I O 1].! 1 k Patented May 31, 1932 -1 mm or CHAR-LES w. UELLER, on ST. roars, mrss'o'onr, ss-remit Ere invisi'nnn search MACHINE COMPANY, F sr. 'LonIs, lvrrsso'nru, A coaieoan'rroit or Marian BLIND s'rrron: snwrns memes Application filed September 14, 1929. serial 1104392339.

a guide for the previously formed seam and this guide is located in the Work clampand extends longitudinally in the line of seam from a point in front of the path of needle penetration to a point in rear thereof. This guide includes relatively fixed vertical side walls and consequently its capacity is thereby limited by the width between these walls.

In practice it frequently occurs in a given factory that a single machine is desired'to be used on extreme weights of material and therefore the principal object of the present invention is to provide a seam guide in a machine of this type which may be spread laterally, or opened, whereby theguide in its normal or closed relation will be of sufficient width to guide a seam formed in relatively li ht weight material and whereby the guide when open will receive and -guide a seam of heavier weight material.

Practice has also demonstrated the fact that in seaming operations of the character above described, the needle in its penetrating movement across the opening in the presser foot through which the plunger projects to form the node of material, is of such a width as to allow the needle when it meets the resistance of the seam to be deflected downwardly out of its true arcuate path with the result that the needle point will strike the opposite edge of the presser foot opening. V

It is therefore another object of the present invention to provide a needle guide which is mounted on the presser foot and which extends centrally across the opening of the foot to thereby prevent the deflection of the needle as above described.

With these and other objects in view which will more fully appear, the nature of the invention will be more clearly understood by following the description, the appended claims, and the several viewsill'ust-rated in the accompanyingdrawings' In the drawings: I. a Figure 1 is a partially left hand elevation of abl'ind StltCh sewing machine embodying I 'my invention, the work presenting mechanism being shown in its elevated or working pos tion,

Figure 2 is a similarcv-iew'showing the work presenting mechanism in its lowered position, a Y F'gurje 3 is a view partly in front'elevationand partly in section showingthe work presenting mechanism in its normal or operating position, 7

Figure 4 is a similarview but showing the work presenting mechanism in its lowered 7 position, 7 a V Figure 5, i's a top plan view of the work clamp, the feed dog and the seam guide, the

latter being shown in-its normal or closed posltlon,

Figure 6 is a similar View but showing thee-seam guide in its open position, Figure 7 is a top plan view of the presser foot, and a Figure 8 is a vertical sectional view through the work presenting mechanism taken on the line offfeed,

Like reference numerals designate corresponding parts throughout the several figures of the drawings.

As previously stated,the present invention relates to improvements on my prior Patent 1,588,132, May 8,1926 and therefore only so much ofthe sewing machine mechanism is disclosed herein as is deemed necessary for a complete understanding of my present invention. a i

The machine includes a base. 5 having a work presenting mechanism indicated as a whole at 6. and a stitching head 7 which is disposed directly above said work presenting mechanism. Rlgidly secured A to, the lower extremityof the stitching head 7 is a presser foot 8 which cooperates with the stitch forming and Work presenting mechanisms.

The stitchmg mechanism includes a needle 9 which in this instance cooperates with a rotary hook 10 to form a line of shuttle stitches. The needle is arranged to oscillate about a horizontal axis and across the line of scam. The presser foot 8 is provided with an opening 11 and cooperating with the presser foot to feed thework is afeed dog 12, a work clamp 13 and a plunger 14. The plunger reciprocates vertically in timed relation to the needle and feed and includes relatively fixed and movable parts 15* and 16 respectively. The upper ends of these parts 15 and 16 are conjointly formed with a gu1ding channel 17 for the reception of the previously formed seam. The plunger engages the under surface of the work on opposite sides of the seam and causes said work to be forced into a node of material which is projected upwardly by the plunger through the presser foot opening 11 into the path of'the needle 9.

The feed dog 12 is of the 4-motion type, thatis, it has a backward and forward move- 'ment, and an up and down movement, and

this compound movement is obtained by the same rock shaft and link connection as is shown and described in my prior patent referred to above. r r

The feed dog 12, the work clamp 13 and the plunger 14 are all supported for vertical movements in a carrier 18 which is mounted on the base 5 and is yieldably held in its upper or operating position by a spring 19. A lever 20 is fulcrumed as'at 21 within the base 5 and one end engages a lug 22 on the carrier 18 and the other end is adapted to be engaged by an operating rod 23 which may be connected to a knee treadle or the like. Thus upon upward movement of the rod 23, the lever 20 will be rocked and the carrier 18 together with the feed dog 12, the work clamp Each member includes a vertical wall 25 which extends in the line of feed, and the inner faces of these walls are downwardly curved toward each other as at 26, 26- so as to coniointly form a guidingchannel for relatively thin material or work. Rigidly sespaced relation. Formed in the guide flanges 27 are horizontally disposed slots 28, 28 and extending through these slots and into the clamp are guide screws 29, 29. Each guide flange 27 is provided with upper and lower guiding flanges 30 and 31 as shown particularly in Figure 8 and these guide flanges cooperate with the front portion of thework clamp 13 to retain the guides in a horizontal plane during opening and closing movements. The guide walls 25, 25' are normally held in their closed position, as shown in Figures 3 and 5, by means of the flat springs 32, 32 which arerespectively secured at their rear ends to the sides of the work clamp by screws 33, 33 and have their forward or free ends engaging the outer ends of the guide flanges 27,27. I 7

Fixed to the work support 5 is an upwardly extending pointed cam 34,the point 35 thereof being disposed directly under the abut 'ing edges of the guide flanges 27 27. The

cam 34 is spaced below the seam guide when presentingmechanism has been lowered and 71 5 the seam guide opened,heavier work can be employed on the same machine as the thicker seam resulting from the heavier work may be readily inserted within the expanded or open seam guide. When the work presenting mechanism is returned to its operative position with the heavier seam located within the guide, the springs 32, 32 will permit the vertical Walls25, 25 of the guide to move to their expanded positions and thereby accommodate the heavier seam.

The presser foot 8 is provided with a needle guide 36 which is disposed centrally within the presser foot opening 11 and is detachably secured to the presser foot by a screw 37. As previously explained this centrally located needle guide prevents downward deflection of the needle as the latter enters the seam and 7 thereby prevents the point of the needle from engaging the opposite side of the presser foot opening andbecoming broken.

From the foregoing, it will be observed that I have provided lateral opening guides for the previously formed seam, means for yieldably retaining the guides against opening movements and means for moving the guides downwardly and for simultaneously opening said guides whereby a previously formed seam may be inserted or. withdrawn or whereby a heavier seam may be inserted within the guides.

It is of course to be understood that the details of structure and arrangements of parts may be variously changed and modified without departing from the spirit and scope of my invention.

I claim:

1. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed scam, the combination of a presser foot and a stitch forming mechanism operating entirely above the work, and a work presenting mechanism disposed below the work and including a seam guide having guide members relatively adjustable laterally to accommodate seams of different widths.

2. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed scam, the combination of a presser foot and a stitch forming mechanism including a needle operating entirely above the work, a work present ing mechanism disposed below the work and including a feed mechanism for presenting the seam to the stitch forming mechanism, means for projecting a node of material into the path of the needle, and a seam guide located in front of the projecting means and automatically adjustable laterally to accommodate seams of different widths.

3. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed seam, the combination of a presser foot and a stitch forming mechanism including a needle operating entirely above the work, a work presenting mechanism disposed below the work and including a feed mechanism for presenting the seam to the stitch forming mechanism, means for projecting a node of material into the path of the needle, a work clamp, and a seam guide mounted on the clamp in front of the projecting means and automatically adjustable laterally to accommodate seams of different widths.

l. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed seam, the combination of a presser foot and a stitch forming mechanism operating entirely above the work, and a work presenting mechanism disposed below the work and including a seam guide adjustable to accommodate seams of different widths, said guide comprising latorally opening guide members, and means for yieldably retaining said guide members against opening.

5. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed. seam, the combination of a presser foot and a stitch forming mechanism including a needle operating entirely above the work, a work presentingmechanism disposed below the work and including afeed mechanism for presenting the seam to the. stitch forming mechanism, means for projecting a node of material into thepath of the needle, and a seam guide located in front of the projecting means and consisting of spaced walls extending in parallelism in the direction of feed, means for supporting said walls for lateral bodily movements in opposite directions, and springs respectively associated with said walls for y1eldably holdmg the latter against opening movements.

6. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed seam, the combination with a presser foot and a stitch forming mechanism operating entirely above the work, a work presenting mechanism disposed belowthe work and including a seam guide adjustable to accommodate seams of different widths, means for yieldably retaining said guide against downward move ment, and means for moving the guide downwardly and for simultaneously opening said' guide.

7. In a blind stitch sewing machine for stitching together the adjacent faces of body guide the cam will, effect opening movement thereof.

8. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a, previously formed seam,

the combination of a presser foot and a stitch forming mechanism including a needle operating entirely above the work, a work presenting mechanism disposed below the work and including a feed mechanism for presenting the seam to the stitch forming mechanism, means for projecting anode of material into the path of the needle, a work clamp, and a seam guide mounted on the clamp in front of the projecting means, said guide including spaced vertical walls extending in the direction of feed and movable towards and from each other, each wall being provided with a guide flange at its front end having sliding engagement with the front end of the work clamp, and flat springs respectively connected to the sides of the clamp and cooperating with the guide flanges to yieldably retain the guide walls against relative outward movement.

9. In a blind stitch sewing machine for stitching together the adjacent faces of body fabrics united by a previously formed seam, the combination with a presser foot and a stitch forming mechanism including a neer dle operating entirely above the work, the foot being provided with an opening for receiving a node of material in position to be stitched, a needle guide fixed to the foot and I located centrally of the opening thereof, and I g a work presenting mechanism disposed below im the work and including means for projecting a node of material upwardly through the opening in the presser foot on opposite sides of said needle guide. i In testimony whereof I hereunto afiix my 15 signature.

CHARLES W. MUELLER 

